On Mon, 2023-08-07 at 10:25 -0400, Chuck Lever wrote: > On Fri, Aug 04, 2023 at 07:16:08PM +0200, Lorenzo Bianconi wrote: > > Introduce rpc_status entry in nfsd debug filesystem in order to dump > > pending RPC requests debugging information. > > > > Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=366 > > Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx> > > Hi Lorenzo, thanks for this new feature. It's been applied to the > nfsd-next branch (for v6.6). I've played with it a little using: > > # watch cat /proc/fs/nfsd/rpc_status > > And it works a lot like a simple "top" command for RPCs. Nice! > > Until this work is merged upstream in a few weeks, there is still an > easy opportunity to refine the information and format of the new > file, if anyone sees the need. The only thing I might think of > adding is a comment in line one like this: > > # version 1 > > to make extending the file format easier. > Good idea. I guess we could also add a header to the file after all too, and just prefix it with '#'. Then any scripting we want to write will always know that any line with a # is part of the header. > Thinking aloud, it occurs to me a similar status file for NFSv4 > callback operations would be great to have. > ACK, that would be nice. I don't think there is a handy list of nfsd4_callback structures though. We'd probably need to add one. > > > --- > > fs/nfsd/nfs4proc.c | 4 +- > > fs/nfsd/nfsctl.c | 9 +++ > > fs/nfsd/nfsd.h | 7 ++ > > fs/nfsd/nfssvc.c | 140 +++++++++++++++++++++++++++++++++++++ > > include/linux/sunrpc/svc.h | 1 + > > net/sunrpc/svc.c | 2 +- > > 6 files changed, 159 insertions(+), 4 deletions(-) > > > > diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c > > index f0f318e78630..b7ad3081bc36 100644 > > --- a/fs/nfsd/nfs4proc.c > > +++ b/fs/nfsd/nfs4proc.c > > @@ -2497,8 +2497,6 @@ static inline void nfsd4_increment_op_stats(u32 opnum) > > > > static const struct nfsd4_operation nfsd4_ops[]; > > > > -static const char *nfsd4_op_name(unsigned opnum); > > - > > /* > > * Enforce NFSv4.1 COMPOUND ordering rules: > > * > > @@ -3628,7 +3626,7 @@ void warn_on_nonidempotent_op(struct nfsd4_op *op) > > } > > } > > > > -static const char *nfsd4_op_name(unsigned opnum) > > +const char *nfsd4_op_name(unsigned opnum) > > { > > if (opnum < ARRAY_SIZE(nfsd4_ops)) > > return nfsd4_ops[opnum].op_name; > > diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c > > index 35d2e2cde1eb..d47b98bad96e 100644 > > --- a/fs/nfsd/nfsctl.c > > +++ b/fs/nfsd/nfsctl.c > > @@ -47,6 +47,7 @@ enum { > > NFSD_MaxBlkSize, > > NFSD_MaxConnections, > > NFSD_Filecache, > > + NFSD_Rpc_Status, > > /* > > * The below MUST come last. Otherwise we leave a hole in nfsd_files[] > > * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops > > @@ -195,6 +196,13 @@ static inline struct net *netns(struct file *file) > > return file_inode(file)->i_sb->s_fs_info; > > } > > > > +static const struct file_operations nfsd_rpc_status_operations = { > > + .open = nfsd_rpc_status_open, > > + .read = seq_read, > > + .llseek = seq_lseek, > > + .release = nfsd_pool_stats_release, > > +}; > > + > > /* > > * write_unlock_ip - Release all locks used by a client > > * > > @@ -1400,6 +1408,7 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc) > > [NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR}, > > [NFSD_V4EndGrace] = {"v4_end_grace", &transaction_ops, S_IWUSR|S_IRUGO}, > > #endif > > + [NFSD_Rpc_Status] = {"rpc_status", &nfsd_rpc_status_operations, S_IRUGO}, > > /* last one */ {""} > > }; > > > > diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h > > index d88498f8b275..50c82bb42e88 100644 > > --- a/fs/nfsd/nfsd.h > > +++ b/fs/nfsd/nfsd.h > > @@ -94,6 +94,7 @@ int nfsd_get_nrthreads(int n, int *, struct net *); > > int nfsd_set_nrthreads(int n, int *, struct net *); > > int nfsd_pool_stats_open(struct inode *, struct file *); > > int nfsd_pool_stats_release(struct inode *, struct file *); > > +int nfsd_rpc_status_open(struct inode *inode, struct file *file); > > void nfsd_shutdown_threads(struct net *net); > > > > void nfsd_put(struct net *net); > > @@ -506,12 +507,18 @@ extern void nfsd4_ssc_init_umount_work(struct nfsd_net *nn); > > > > extern void nfsd4_init_leases_net(struct nfsd_net *nn); > > > > +const char *nfsd4_op_name(unsigned opnum); > > #else /* CONFIG_NFSD_V4 */ > > static inline int nfsd4_is_junction(struct dentry *dentry) > > { > > return 0; > > } > > > > +static inline const char *nfsd4_op_name(unsigned opnum) > > +{ > > + return "unknown_operation"; > > +} > > + > > static inline void nfsd4_init_leases_net(struct nfsd_net *nn) { }; > > > > #define register_cld_notifier() 0 > > diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c > > index 97830e28c140..5e115dbbe9dc 100644 > > --- a/fs/nfsd/nfssvc.c > > +++ b/fs/nfsd/nfssvc.c > > @@ -1057,6 +1057,15 @@ int nfsd_dispatch(struct svc_rqst *rqstp) > > if (!proc->pc_decode(rqstp, &rqstp->rq_arg_stream)) > > goto out_decode_err; > > > > + /* > > + * Release rq_status_counter setting it to an odd value after the rpc > > + * request has been properly parsed. rq_status_counter is used to > > + * notify the consumers if the rqstp fields are stable > > + * (rq_status_counter is odd) or not meaningful (rq_status_counter > > + * is even). > > + */ > > + smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter | 1); > > + > > rp = NULL; > > switch (nfsd_cache_lookup(rqstp, &rp)) { > > case RC_DOIT: > > @@ -1074,6 +1083,12 @@ int nfsd_dispatch(struct svc_rqst *rqstp) > > if (!proc->pc_encode(rqstp, &rqstp->rq_res_stream)) > > goto out_encode_err; > > > > + /* > > + * Release rq_status_counter setting it to an even value after the rpc > > + * request has been properly processed. > > + */ > > + smp_store_release(&rqstp->rq_status_counter, rqstp->rq_status_counter + 1); > > + > > nfsd_cache_update(rqstp, rp, rqstp->rq_cachetype, statp + 1); > > out_cached_reply: > > return 1; > > @@ -1149,3 +1164,128 @@ int nfsd_pool_stats_release(struct inode *inode, struct file *file) > > mutex_unlock(&nfsd_mutex); > > return ret; > > } > > + > > +static int nfsd_rpc_status_show(struct seq_file *m, void *v) > > +{ > > + struct inode *inode = file_inode(m->file); > > + struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); > > + int i; > > + > > + rcu_read_lock(); > > + > > + for (i = 0; i < nn->nfsd_serv->sv_nrpools; i++) { > > + struct svc_rqst *rqstp; > > + > > + list_for_each_entry_rcu(rqstp, > > + &nn->nfsd_serv->sv_pools[i].sp_all_threads, > > + rq_all) { > > + struct { > > + struct sockaddr daddr; > > + struct sockaddr saddr; > > + unsigned long rq_flags; > > + const char *pc_name; > > + ktime_t rq_stime; > > + __be32 rq_xid; > > + u32 rq_prog; > > + u32 rq_vers; > > + /* NFSv4 compund */ > > + u32 opnum[NFSD_MAX_OPS_PER_COMPOUND]; > > + u8 opcnt; > > + } rqstp_info; > > + unsigned int status_counter; > > + char buf[RPC_MAX_ADDRBUFLEN]; > > + int j; > > + > > + /* > > + * Acquire rq_status_counter before parsing the rqst > > + * fields. rq_status_counter is set to an odd value in > > + * order to notify the consumers the rqstp fields are > > + * meaningful. > > + */ > > + status_counter = smp_load_acquire(&rqstp->rq_status_counter); > > + if (!(status_counter & 1)) > > + continue; > > + > > + rqstp_info.rq_xid = rqstp->rq_xid; > > + rqstp_info.rq_flags = rqstp->rq_flags; > > + rqstp_info.rq_prog = rqstp->rq_prog; > > + rqstp_info.rq_vers = rqstp->rq_vers; > > + rqstp_info.pc_name = svc_proc_name(rqstp); > > + rqstp_info.rq_stime = rqstp->rq_stime; > > + rqstp_info.opcnt = 0; > > + memcpy(&rqstp_info.daddr, svc_daddr(rqstp), > > + sizeof(struct sockaddr)); > > + memcpy(&rqstp_info.saddr, svc_addr(rqstp), > > + sizeof(struct sockaddr)); > > + > > +#ifdef CONFIG_NFSD_V4 > > + if (rqstp->rq_vers == NFS4_VERSION && > > + rqstp->rq_proc == NFSPROC4_COMPOUND) { > > + /* NFSv4 compund */ > > + struct nfsd4_compoundargs *args = rqstp->rq_argp; > > + > > + rqstp_info.opcnt = args->opcnt; > > + for (j = 0; j < rqstp_info.opcnt; j++) { > > + struct nfsd4_op *op = &args->ops[j]; > > + > > + rqstp_info.opnum[j] = op->opnum; > > + } > > + } > > +#endif /* CONFIG_NFSD_V4 */ > > + > > + /* > > + * Acquire rq_status_counter before reporting the rqst > > + * fields to the user. > > + */ > > + if (smp_load_acquire(&rqstp->rq_status_counter) != status_counter) > > + continue; > > + > > + seq_printf(m, > > + "0x%08x 0x%08lx 0x%08x NFSv%d %s %016lld", > > + be32_to_cpu(rqstp_info.rq_xid), > > + rqstp_info.rq_flags, > > + rqstp_info.rq_prog, > > + rqstp_info.rq_vers, > > + rqstp_info.pc_name, > > + ktime_to_us(rqstp_info.rq_stime)); > > + seq_printf(m, " %s", > > + __svc_print_addr(&rqstp_info.saddr, buf, > > + sizeof(buf), false)); > > + seq_printf(m, " %s", > > + __svc_print_addr(&rqstp_info.daddr, buf, > > + sizeof(buf), false)); > > + for (j = 0; j < rqstp_info.opcnt; j++) > > + seq_printf(m, " %s", > > + nfsd4_op_name(rqstp_info.opnum[j])); > > + seq_puts(m, "\n"); > > + } > > + } > > + > > + rcu_read_unlock(); > > + > > + return 0; > > +} > > + > > +/** > > + * nfsd_rpc_status_open - open routine for nfsd_rpc_status handler > > + * @inode: entry inode pointer. > > + * @file: entry file pointer. > > + * > > + * nfsd_rpc_status_open is the open routine for nfsd_rpc_status procfs handler. > > + * nfsd_rpc_status dumps pending RPC requests info queued into nfs server. > > + */ > > +int nfsd_rpc_status_open(struct inode *inode, struct file *file) > > +{ > > + struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); > > + > > + mutex_lock(&nfsd_mutex); > > + if (!nn->nfsd_serv) { > > + mutex_unlock(&nfsd_mutex); > > + return -ENODEV; > > + } > > + > > + svc_get(nn->nfsd_serv); > > + mutex_unlock(&nfsd_mutex); > > + > > + return single_open(file, nfsd_rpc_status_show, inode->i_private); > > +} > > diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h > > index fe1394cc1371..542a60b78bab 100644 > > --- a/include/linux/sunrpc/svc.h > > +++ b/include/linux/sunrpc/svc.h > > @@ -270,6 +270,7 @@ struct svc_rqst { > > * net namespace > > */ > > void ** rq_lease_breaker; /* The v4 client breaking a lease */ > > + unsigned int rq_status_counter; /* RPC processing counter */ > > }; > > > > #define SVC_NET(rqst) (rqst->rq_xprt ? rqst->rq_xprt->xpt_net : rqst->rq_bc_net) > > diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c > > index 587811a002c9..44eac83b35a1 100644 > > --- a/net/sunrpc/svc.c > > +++ b/net/sunrpc/svc.c > > @@ -1629,7 +1629,7 @@ const char *svc_proc_name(const struct svc_rqst *rqstp) > > return rqstp->rq_procinfo->pc_name; > > return "unknown"; > > } > > - > > +EXPORT_SYMBOL_GPL(svc_proc_name); > > > > /** > > * svc_encode_result_payload - mark a range of bytes as a result payload > > -- > > 2.41.0 > > > -- Jeff Layton <jlayton@xxxxxxxxxx>
